Where did the name 'Sai' come from, according to the texts?

The name 'Sai' was bestowed upon Baba at the moment of his arrival in Shirdi. According to the account in Chapter 5, when the wedding party that Baba accompanied arrived, they stopped near the Khandoba temple. As the young Fakir, who was Baba, stepped down from the cart, he was seen by a devotee named Mahalsapati. Mahalsapati instinctively went forward and greeted him with the words "Ya Sai," which translates to "Welcome, Sai." This respectful salutation stuck, and from that time forward, people began to call him 'Sai,' making it his known name.